The Dark Knights – ATK’s Advanced Boosters for SLS revealed

A presentation overviewing ATK’s preliminary proposal for the upcoming advanced booster competition for Space Launch System (SLS) claims the new motor will be 40 percent cheaper and 23.5 percent more reliable than the five segment booster that will initially launch with the Heavy Lift Launch Vehicle (HLV) – all while adding 15.1mT of additional performance.

The DM-3 incorporated several performance-based improvements to the designs of the first two development motors. Additionally, the core of DM-3 was heated to 90 degrees Fahrenheit for this full-duration firing to verify the motor’s performance at high temperatures.

ATK are already deep into preparations for the first qualification firing of the five segment booster, with QM-1 set to take place in May, 2013.

As part of enabling this evolution, a competition will decide between numerous proposals that will create an “advanced booster” option for SLS, which will be implemented on the Block 1A (or Block 1B – depending on the configuration), prior to its role with the Block II from its first launch.

One such proposal – which is currently being worked on under NASA’s SLS Advanced Booster Engineering Demonstration and/or Risk Reduction (ABEDRR) procurement – was reported on by this site after Dynetics, Inc. and Pratt & Whitney Rocketdyne (PWR) formed a team “to offer an affordable booster approach that meets the evolved capabilities of the SLS” – and presented their overview at the 63rd International Astronautical Congress, Naples, Italy in October, 2012.

ATK’s proposal – outlined in a presentation acquired by L2 – builds on their legacy, with a motor that is “advanced” on several levels, by “provid(ing) NASA the capability for the SLS to achieve 130 mT payload with significant margin, utilizing a booster that is 40 percent less expensive and 24 percent more reliable than the current SLS booster.

“Some of the characteristics of the Advanced Booster include features that have been identified by NASA as important for the next-generation booster are: an energetic propellant to improve performance and reduce cost, a composite case using low cost fiber/resin, electric Thrust Vector Control (TVC), and an adaptable core attach design to minimize interface concerns.”

ATK cite advanced manufacturing techniques and streamlined processes – combined with an innovative design that includes the nose cone reshaped to reduce aerodynamic loads on the core stage – as a major part of the 40 percent reduction in costs when compared to the five-segment SRBs.

ATK are also proposing to reduce the number of segments – back to four – to improve processing at launch site, along with simplified forward and aft structures and increased comparability with the overall vehicle avionics architecture.

A key line in the presentation cites the Advanced Booster “will provide 42 percent of SLS vehicle impulse while making up only 18 percent of the total vehicle propulsion cost.”

Charts provided in the presentation expand on areas where performance will be improved, all while reducing costs when compared to the five segment motor.

This can be clearly seen in examples such as the use of the composite casings, which provide a 4,128lbm payload capability improvement. The simplified stage assemblies comparison cites the saving of 480 man hours – a 50 percent reduction in the man hours required on the five segment motor.

Most impressive is the improved ballistics, with the higher ISP density of the propellent boosting payload performance by nearly 25,000lbm, yet saving $9.2m in costs per booster.

However, what can’t be estimated is ATK’s foothold as the provider of boosters for NASA’s human space flight program for the past 30 years. A continuation with the familiarity of the solid motors is continually classed as the favored option by SLS sources.

(Images: Via NASA and L2 content from L2′s SLS specific L2 section, which includes, presentations, videos, graphics and internal – interactive with actual SLS engineers – updates on the SLS and HLV, available on no other site.)

(L2 is – as it has been for the past several years – providing full exclusive SLS and Exploration Planning coverage. To join L2, click here: http://www.nasaspaceflight.com/l2/)